Across a wide range of tasks, research has shown that people make poor probabilistic predictions of future events. Recently, the U.S. Intelligence Community sponsored a series of forecasting tournaments designed to explore the best strategies for generating accurate subjective probability estimates of geopolitical events. In this article, we describe the winning strategy: culling off top performers each year and assigning them into elite teams of superforecasters. Defying expectations of regression toward the mean 2 years in a row, superforecasters maintained high accuracy across hundreds of questions and a wide array of topics. We find support for four mutually reinforcing explanations of superforecaster performance: (a) cognitive abilities and styles, (b) task-specific skills, (c) motivation and commitment, and (d) enriched environments. These findings suggest that superforecasters are partly discovered and partly created-and that the high-performance incentives of tournaments highlight aspects of human judgment that would not come to light in laboratory paradigms focused on typical performance.

Beck’s insight—that beliefs about one’s self, future, and environment shape behavior—transformed depression treatment. Yet environment beliefs remain relatively understudied. We introduce a set of environment beliefs—primal world beliefs or primals—that concern the world’s overall character (e.g., the world is interesting, the world is dangerous). To create a measure, we systematically identified candidate primals (e.g., analyzing tweets, historical texts, etc.); conducted exploratory factor analysis (N = 930) and two confirmatory factor analyses (N = 524; N = 529); examined sequence effects (N = 219) and concurrent validity (N = 122); and conducted test-retests over 2 weeks (n = 122), 9 months (n = 134), and 19 months (n = 398). The resulting 99-item Primals Inventory (PI-99) measures 26 primals with three overarching beliefs—Safe, Enticing, and Alive (mean α = .93)—that typically explain ∼55% of the common variance. These beliefs were normally distributed; stable (2 weeks, 9 months, and 19 month test-retest results averaged .88, .75, and .77, respectively); strongly correlated with many personality and wellbeing variables (e.g., Safe and optimism, r = .61; Enticing and depression, r = −.52; Alive and meaning, r = .54); and explained more variance in life satisfaction, transcendent experience, trust, and gratitude than the BIG 5 (3%, 3%, 6%, and 12% more variance, respectively). In sum, the PI-99 showed strong psychometric characteristics, primals plausibly shape many personality and wellbeing variables, and a broad research effort examining these relationships is warranted.

R ecently, the National Science Foundation projected that the current 10-billion dollar nanotechnology sector will employ 2 million workers, including as many as 1 million workers in the United States. 1 It is expected that over 80% of the jobs created in this sector will require trained individuals in nanoscience. However, little training at the undergraduate level has been initiated to provide highly specialized scientists to this rapidly developing field. The proposed laboratory experiment, which was implemented for both undergraduate and graduate student laboratories in physical chemistry and nanotechnology, addresses the future projected demand.In 1998, G. C. Weaver and K. Norrod proposed an undergraduate laboratory to introduce the surface-enhanced Raman scattering (SERS) effect and to extend the scope of the Raman theory normally covered in physical chemistry courses. 2 A Raman-active molecule, pyridine, was adsorbed on colloidal silver nanoparticles (AgNPs) to demonstrate the large increase in Raman signal. Although successful, the SERS experiment did not estimate the analytical enhancement factor (AEF) and surface enhancement factor (SEF), the most important values for characterizing the SERS effect. 3,4 The Raman signal enhancement of 100À300 times was simply determined by calculating the ratio of integrated areas for specific vibrational modes of pyridine adsorbed on AgNPs and in solution. However, the pyridine concentrations (1.0 Â 10 À1 M for normal Raman and 6.25 Â 10 À3 M for SERS measurements) were extremely large when compared with the trace amounts of analyte that are now detected via SERS. In the following years, theoretical and experimental studies have demonstrated that single-molecule SERS-based detection and identification can be achieved under favorable circumstances. 5,6 Because of the enormous enhancement, SERS found numerous cutting-edge applications in medical, biological, chemical, military defense, homeland security, pharmacological, and environmental settings. 7À9 Most SERSbased detection and identification applications require an accurate determination of the magnitude of the signal enhancement.In this experiment, Raman and fluorescence spectrophotometers were employed to estimate the analytical and surface enhancement factors for rhodamine 6G adsorbed on a Creighton colloid. 10 Among the many kinds of SERS-active substrates, silver colloids are known to lead to huge enhancement factors and to enable single-molecule SERS experiments. 5À7,11 The Creighton method has been widely used for its simplicity, relative low cost, accessibility, and time efficiency. These parameters were critical in designing a feasible experiment for a laboratory. Not surprisingly, in 2007, Solomon et al. implemented the Creighton procedure for the synthesis of colloidal AgNPs as a new laboratory experiment for a general chemistry class. 12

Numerous nanoparticle (NP) fabrication methodologies employ "bottom-up" syntheses, which may result in heterogeneous mixtures of NPs or may require toxic capping agents to reduce NP polydispersity. Tangential flow filtration (TFF) is an alternative "green" technique for the purification, concentration, and size-selection of polydisperse NP suspensions or colloids, in that it allows for real-time analysis and reduces the usage of additional solvent and post-synthetic reagents. Upper-division undergraduate and graduate students in engineering and chemistry successfully applied a three-step TFF process to reduce the polydispersity of Creighton colloidal silver nanoparticles (AgNPs). UV−vis absorption spectroscopy in conjunction with the Lambert−Beer law and Mie's solutions to the Maxwell equations were employed to rapidly estimate the concentration and size of nanosilver in each TFF-fractionated colloidal sample using the localized surface plasmon resonance (LSPR) of AgNPs. A thorough emphasis on "green" nanochemistry and its underlying principles were also provided to educate the next generation of environmentally conscious nanochemists and nanoengineers for the ever-expanding nanosectors. The overall laboratory experience was perceived as intellectually stimulating and was highly rated in the student evaluations. This interdisciplinary experiment may be implemented in various nanotechnology, physical, or analytical courses.

Scholars, practitioners, and pundits often leave their assessments of uncertainty vague when debating foreign policy, arguing that clearer probability estimates would provide arbitrary detail instead of useful insight. We provide the first systematic test of this claim using a data set containing 888,328 geopolitical forecasts. We find that coarsening numeric probability assessments in a manner consistent with common qualitative expressions-including expressions currently recommended for use by intelligence analysts-consistently sacrifices predictive accuracy. This finding does not depend on extreme probability estimates, short time horizons, particular scoring rules, or individual attributes that are difficult to cultivate. At a practical level, our analysis indicates that it would be possible to make foreign-policy discourse more informative by supplementing natural language-based descriptions of uncertainty with quantitative probability estimates. More broadly, our findings advance long-standing debates over the nature and limits of subjective judgment when assessing social phenomena, showing how explicit probability assessments are empirically justifiable even in domains as complex as world politics.